Clutch engagement ramps for torque converter

ABSTRACT

A torque converter including an axis of rotation and a flange rotatable about the axis of rotation is disclosed. The torque converter includes a turbine shell independently rotatable about the axis of rotation relative to the flange. A first plate, disposed between the flange and the turbine shell, may be fixed to the turbine shell. A second plate, disposed between the flange and the turbine shell, may be radially outward relative to the first plate. The torque converter further includes a cover having an inner surface and a third plate disposed between the flange and the cover. The first plate may include at least one ramp protruding in an axial direction toward the flange, wherein the ramp is rotatably engageable with the flange for urging the flange axially in a direction toward the cover, and for transmitting an axial force for urging a clutch to engage.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional of U.S. application Ser. No. 14/920,243filed Oct. 22, 2015, which, in turn, claims the benefit of U.S.provisional application Ser. No. 62/157,661 filed May 6, 2015 and U.S.provisional application Ser. No. 62/084,788 filed Nov. 26, 2014, thedisclosures of which are hereby incorporated in their entirety byreference herein.

TECHNICAL FIELD

The present disclosure relates generally to a damper assembly featuringramps for engaging a clutch. In particular, the damper ramps arerotatably engageable within the damper assembly to transmit an axialforce for urging a torque converter clutch to engage.

BACKGROUND

Torque converter turbines incorporating lockup clutches are known.Examples are shown in commonly-assigned U.S. Pat. No. 7,445,099 inaddition to U.S. Patent Publication Nos. US2013/0230385A1 andUS2014/0097055A1, each hereby incorporated by reference herein.

BRIEF SUMMARY

Example aspects broadly comprise a turbine damper assembly comprising:an axis of rotation; first and second cover plates arranged to receivetorque; a flange rotatable about the axis of rotation and axiallydisposed between the first and second cover plates; at least oneresilient element, at least partially disposed axially between the firstand second cover plates, for transmitting a torque force between theflange and the cover plates; a first axial gap, disposed between theflange and the first cover plate, having a first width; a second axialgap, disposed between the flange and the second cover plate, having asecond width; at least one of the first cover plate, the second coverplate, or the flange having at least one ramp protruding in an axialdirection, the ramp rotatably engageable with another of the at leastone of the first cover plate, the second cover plate, or the flange todecrease the first axial gap, increase the second axial gap, andtransmit an axial force for urging a clutch to engage. In an exampleaspect, the second cover plate includes the ramp and the flange isrotatable about the axis of rotation in a first circumferentialdirection relative to the first and second cover plates to engage the atleast one ramp to decrease the first axial gap and increase the secondaxial gap. In an example aspect, the flange is rotatable about the axisof rotation in a second circumferential direction, opposite the firstcircumferential direction, to engage the at least one ramp to decreasethe first axial gap and increase the second axial gap to increase clutchcapacity. In an example aspect, the second cover plate includes the atleast one ramp and the flange comprises an outer circumferential edgehaving at least one tab protruding therefrom, the tab rotatablyengageable with the ramp.

Other example aspects broadly comprise torque converter comprising: anaxis of rotation; a cover, a turbine comprising a turbine shell and aplurality of blades; an impeller comprising an impeller shell and aplurality of blades; a stator comprising a plurality of blades; a damperassembly comprising: first and second cover plates arranged to receivetorque: at least one of the first or second cover plates having at leastone ramp protruding in an axial direction; and; at least one of thefirst or second cover plates fixedly attached to the turbine shell; aflange, axially supported by the cover and axially disposed between thefirst and second cover plates; at least one resilient element, at leastpartially disposed axially between the first and second cover plates,for transmitting a torque force between the flange and the cover plates;and, a clutch including: a clutch plate; and, an apply plate. In anexample aspect, the damper assembly further includes a first axial gap,disposed between the flange and the first cover plate, having a firstwidth and a second axial gap, disposed between the flange and the secondcover plate, having a second width. In an example aspect, the at leastone ramp is rotatably engageable with the flange to decrease the firstaxial gap, increase the second axial gap, and transmit an axial forcefor urging the clutch to engage. In an example aspect, the torqueconverter further comprises a friction material disposed between theapply plate and the clutch plate, wherein the friction material isattached to one of the apply plate or the clutch plate or both. In anexample aspect, the impeller shell includes the apply plate and theturbine shell includes the clutch plate. In an example aspect, theflange comprises an outer circumferential edge having at least one tabprotruding therefrom in a radial direction, the tab rotatably engageablewith the ramp. In an example aspect, the tab comprises: first and secondflat surfaces, first and second side surfaces having first and secondthicknesses, and, at least one tapered surface, connecting the secondflat surface to the second side surface, wherein the at least onetapered surface is arranged for rotatably engaging the ramp. In anexample aspect, the ramp further includes an apex portion and a riseportion, wherein the rise portion is rotatably engageable with thetapered surface. In an example aspect, the apex portion includes a flatportion for maintaining engagement with the tab. In an example aspect,the flange supported by the cover further includes a bushing, a thrustwasher, or both disposed between the flange and the cover. In an exampleaspect, the flange is arranged for direct connection to a transmissioninput shaft. In an example aspect, the flange is rotatable in a firstcircumferential direction in coast mode to: engage the ramp, react onthe cover; and, press or move one of the first or second cover plates todisplace or deflect the turbine shell in an axial direction towards theimpeller thus urging the clutch plate to touch the apply plate; or, isrotatable in a second circumferential direction, opposite to the firstcircumferential direction, in drive mode to: engage the ramp, react onthe cover, and, press or move one of the first or second cover plates todeflect or displace the turbine shell in an axial direction towards theimpeller thus increasing clutch capacity.

Other example aspects broadly comprise a torque converter comprising: anaxis of rotation; a turbine comprising a turbine shell and a pluralityof blades; an impeller comprising an impeller shell and a plurality ofblades; a housing comprising a cover and the impeller shell; a statorcomprising a plurality of blades; a damper assembly comprising: firstand second cover plates arranged to receive torque; a flange rotatableabout the axis of rotation, axially supported by the cover, and axiallydisposed between the first and second cover plates; at least oneresilient element, at least partially disposed axially between the firstand second cover plates, for transmitting a torque force between theflange and the cover plates; at least one of the first cover plate, thesecond cover plate, or the flange having at least one ramp protruding inan axial direction, the ramp rotatably engageable with another of the atleast one of the first cover plate, the second cover plate, or theflange; a first axial distance, as measured between an inner surface ofthe cover and a first radial surface of the flange, remains unchanged asthe ramp is rotatably engaged; a second axial distance, as measuredbetween the inner surface of the cover and a second radial surface ofthe second cover plate, increases as the ramp is rotatably engaged; and,a clutch including: a clutch plate; and, an apply plate. In an exampleaspect, the turbine shell is fixed to the second cover plate and, as theramp is rotatably engaged, the turbine shell is displaced in an axialdirection towards the impeller. In an example aspect, the turbine shellincludes the clutch plate. In an example aspect, the clutch is engagedas the ramp is rotatably engaged.

Other example aspects broadly comprise a torque converter comprising: anaxis of rotation; a flange rotatable about the axis of rotation; aturbine shell independently rotatable about the axis of rotationrelative to the flange; a first plate, disposed between the flange andthe turbine shell, fixed to the turbine shell; a second plate, disposedbetween the flange and the turbine shell, radially outward relative tothe first plate; a cover having an inner surface; a third plate,disposed between the flange and the cover, at least one resilientelement, at least partially disposed axially between the second andthird plates and radially outward relative to the first plate, fortransmitting a torque force between the flange and the second and thirdplates; a first axial gap, disposed between the flange and the secondplate, having a first width; a second axial gap, disposed between theflange and the third plate, having a second width; the first platehaving at least one ramp protruding in an axial direction toward theflange, the ramp rotatably engageable with the flange for urging theflange axially in a direction toward the cover, and for transmitting anaxial force for urging a clutch to engage. In an example aspect, thefirst plate is stamped and hardened. In an example aspect, the firstplate is fixed to the turbine shell via a weld or a rivet. In an exampleaspect, the first plate is an annular plate and is cut or lanced tointegrally form the at least one ramp having a first axial height. In anexample aspect, the flange is rotatable about the axis of rotation in afirst circumferential direction relative to the second and third platesto engage the at least one ramp. In an example aspect, the flange isrotatable about the axis of rotation in a second circumferentialdirection, opposite the first circumferential direction, to engage theat least one ramp to increase clutch capacity. In an example aspect, thesecond plate is fixed to the turbine shell. In an example aspect, thefirst and second plates are integrally formed. In an example aspect, thethird plate includes a radially outward portion disposed between twopendulum masses.

Other example aspects broadly comprise a torque converter comprising: anaxis of rotation; first and second cover plates arranged to receivetorque; a flange rotatable about the axis of rotation; a turbine shellindependently rotatable about the axis of rotation relative to theflange; an optional third plate, disposed between the flange and theturbine shell, fixed to the turbine shell; at least one resilientelement, at least partially disposed axially between the first andsecond cover plates and radially outward relative to the third plate,for transmitting a torque force between the flange and the first andsecond cover plates; a first axial gap, disposed between the flange andthe first cover plate, having a first width; a second axial gap,disposed between the flange and the second cover plate, having a secondwidth; one of the first cover plate, the second cover plate, or thethird plate having at least one ramp protruding in an axial directiontoward the flange, the ramp rotatably engageable with the flange forurging the flange axially in a direction toward the cover, and fortransmitting an axial force for urging a clutch to engage.

BRIEF DESCRIPTION OF THE DRAWINGS

The nature and mode of operation of the present disclosure will now bemore fully described in the following detailed description of thepresent disclosure taken with the accompanying drawing figures, inwhich:

FIG. 1 illustrates a partial cross sectional side view of a torqueconverter including a damper assembly having clutch engagement damperramps according to an example aspect.

FIG. 2 illustrates a perspective view of a damper assembly having clutchengagement damper ramps according to an example aspect.

FIG. 3 illustrates a perspective view of a cover plate including rampsaccording to an example aspect.

FIG. 4 illustrates a perspective view of a flange including tabsaccording to an example aspect.

FIGS. 5A-5C illustrate a slice through a damper assembly according to anexample aspect as viewed near the outer circumference of the assembly inorder to schematically illustrate ramp engagement features at varyingrotational positions. FIG. 5A shows a cover plate ramp not yet engagedwith a flange tab. FIG. 5B shows a cover plate ramp and flange tab justbefore engagement according to an example aspect. FIG. 5C shows a coverplate ramp fully engaged with a flange tab according to an exampleaspect.

FIG. 6A illustrates a partial cross-sectional view of a damper assemblyincluding a flange disposed between two cover plates in an examplealternative aspect. FIG. 6B illustrates a partial top view of a damperassembly wherein a cover plate is lanced to form a ramp according to anexample aspect.

FIG. 7 illustrates a partial cross-sectional view of a damper assemblyshowing a cover plate is lanced and a flange is coined according to anexample alternative aspect.

FIG. 8A illustrates a partial cross-sectional view of a damper assemblyshowing a flange disposed between two cover plates according to anexample alternative aspect. FIG. 8B shows a partial top view of a damperassembly wherein a cover plate is lanced to form an elongated fingerramp according to an example aspect.

FIG. 9 illustrates a cross-sectional view of a torque converterincluding a turbine damper assembly comprising a hardened ramp plateaccording to another example aspect.

FIG. 10 illustrates a partial cross-sectional view of the torqueconverter as shown in FIG. 9 according to an example aspect.

FIG. 11 illustrates a perspective view of a hardened ramp plate as shownin FIGS. 9 and 10 according to an example aspect.

FIG. 12 illustrates a top view of a flange as shown in FIGS. 9 and 10according to an example aspect.

FIG. 13 illustrates a cross-sectional view of torque converter 210wherein the turbine damper assembly includes coast engagement ramp plateaccording to an example aspect.

FIG. 14 illustrates a partial cross-sectional view of a flange engagingwith the coast engagement ramp plate ramps of FIG. 13 according to anexample aspect.

DETAILED DESCRIPTION

At the outset, it should be appreciated that like drawing numbersappearing in different drawing views identify identical, or functionallysimilar, structural elements. Furthermore, it is understood that thispresent disclosure is not limited only to the particular embodiments,methodology, materials and modifications described herein, and as suchmay, of course, vary. It is also understood that the terminology usedherein is for the purpose of describing particular aspects only, and isnot intended to limit the scope of the present disclosure, which islimited only by the appended claims.

Unless defined otherwise, all technical and scientific terms used hereinhave the same meaning as commonly understood to one of ordinary skill inthe art to which this present disclosure belongs. Although any methods,devices or materials similar or equivalent to those described herein canbe used in the practice or testing of the present disclosure, thefollowing example methods, devices, and materials are now described.

The axial forces between a turbine and an impeller in a torque converterare dependent on the direction of fluid flow in the torus. In the drivecondition, the turbine pulls towards the impeller. In the coastcondition, the turbine pushes away from the impeller. For torqueconverters with turbine clutches, for example, clutch engagement occursmore readily in drive mode. However, in coast mode the turbine is thrustin the opposite direction due to hydrodynamic forces thereby makingclutch engagement more problematic. The thrust force in coast conditioncauses a larger gap between the impeller and turbine at the frictionsurface. The increased gap at the friction surface may not allowsufficient flow restriction to build up pressure against the coastthrust force in order to close the clutch during coast engagement. Theseforces must be overcome to fully engage the clutch. In coast, once thetouching of the plates is achieved, the flow restriction is such thatsufficient apply pressure is available to engage the clutch.

For improved clutch engagement for torque converters with turbineclutches, in an example aspect, a flange and a cover plate pair arearranged to be axially displaceable, at least locally or partially, toexpand thus encouraging engagement of a torque converter turbine pistonlockup clutch. Advantageously, this arrangement may be utilized in thecoast condition and is conversely also applicable to the drive conditionwhere necessary. For example, extra clutch capacity may be required indrive at higher engine torque conditions and/or when the transmissioncannot supply enough pressure for full clutch lockup.

In an example aspect, at least one of the components of the damperassembly, i.e. the first cover plate, the second cover plate, and/or theflange, includes at least one ramp. As the damper winds up in eithercoast or drive modes and as tailored to specific torque converterconditions, the flange rotates relative to the cover plate(s) so thatthe ramp presses against the oppositely facing component until axialexpansion of the damper assembly, at least locally, is achieved. As thedamper assembly expands, the flange reacts on the cover or housing,which is fixed, in other words pressing against the cover thus urgingthe at least one cover plate to force the clutch to close. In an exampleaspect, the clutch is a turbine piston for engagement with an impeller.

The following description is made with reference to FIGS. 1 through 5C.FIG. 1 illustrates a partial cross sectional side view of a torqueconverter including a damper assembly having clutch engagement damperramps according to an example aspect. Torque converter 10 includes frontcover 12 for connecting to a crankshaft of internal combustion engine 5via stud 11 and rear cover 16, also referred to as impeller shellinterchangeably herein, for an impeller 18. Impellers are also referredto in the art interchangeably as ‘pump’. Front cover 12 and rear cover16 are fastened together via weld 14. Cover 12 includes cover pilotportion 90. Torque converter 10 also includes turbine 20, turbine shell22, and stator 32 between turbine 20 and impeller 18. Turbines andimpellers, as is known in the art, include a plurality of blades 21 and19, respectively. Torque converter 10 of FIG. 1 includes clutch 15including extended portion 23 of turbine shell 22, also referred to asturbine piston 23 or clutch plate 23 interchangeably herein. In anexample aspect, impeller shell 16 includes inner portion 17, alsoreferred to as apply plate 17 interchangeably herein. Friction material25 is disposed between clutch plate 23 and apply plate 17. Frictionmaterial 25 is attached to clutch plate 23, to apply plate 17, or toboth.

Torque converter 10 includes one-way clutch 30, which supports stator 32and includes inner race 88, roller 92, and outer race 94. Side plate 36holds one-way clutch 30 in place within stator 32. Thrust bearing 34 issituated between side plate 36 and impeller shell 16. Torque converter10 also includes damper assembly 40, which is connected to and drivableby turbine 20, and is positioned between turbine 20 and front cover 12.Damper assembly 40 includes springs 42, flange 46, first cover plate 24,and second cover plate 26, fixed to turbine shell 22 via rivet 48.Springs 42 are at least partially disposed between cover plates 24 and26. Cover plates 24 and 26 may include window openings 27 and wings 29(shown in FIG. 3) as are known in the art to accommodate, position, andaxially support the springs. Damper assembly 40 optionally includesbushing 44 and thrust washer 28. In an example aspect, flange 46 axiallythrusts against or is axially supported by cover 12 via bushing 44supporting thrust washer 28. Thrust washer 28 is attached to cover 12 bymethods known in the art, such as projection welding, for example. Theclutch engagement damper assembly 40 including ramps of FIG. 1 is inclutch open mode, in other words, ramps are not engaged and first axialgap g1 is defined as the space between first cover plate 24 and flange46 second axial gap g2 is defined as the space between flange 46 andsecond cover plate 26. In open clutch mode, clutch plate 23 does nottouch apply plate 17, the space disposed therebetween is shown asclearance 13. Moreover, the first axial gap g1 decreases and secondaxial gap g2 increases upon ramp engagement. Flange 46 remainsstationary, in other words is not axially displaced during rampengagement, as displacement of flange 46 is restricted by cover 12.Therefore, flange 46 reacts on cover 12, which is fixed, to apply athrust force (F as shown in FIG. 5C) to second cover plate 26, which inturns applies a thrust force to turbine shell 22 at rivet 48, and thusapplies a thrust force at clutch plate 23 to close clearance 13 toengage clutch 15. In other words, clearance 13 between clutch plate 23and apply plate 17 equals zero. Clutch 15 is engaged when clutch plate23 and apply plate 17 touch; or in an example aspect, wherein the clutchfurther comprises friction material 25, the clutch plate 23 touchesfriction material 25 which touches apply plate 17 to engage clutch 15.

Torque converter 10, as shown in FIG. 1, further includes hub 80 fixedto flange 46, bushing 86, weld 96, and hub 98. Transmission componentsspline, input shaft, and stator shaft are not shown. Hub 80 is splinedto the input shaft and inner race 88 is splined to the stator shaft.Bushing 86 positions and at least partially seals turbine shell 22 onthe input shaft. Torque converter 10 includes axis of rotation A, alsosimply referred to as axis A. First axial direction AD1 is opposite tosecond axial direction AD2. First radial direction RD1 is opposite tosecond radial direction RD2. First circumferential direction CD1 isopposite to second circumferential direction CD2.

FIG. 2 shows a perspective view of the damper assembly according to anexample aspect. Damper assembly 40, also referred to hereininterchangeably as turbine damper assembly, comprises axis of rotationA, cover plates 24 and 26 arranged to receive torque and connected byspacer rivets 31. Spacer rivets 31 maintain a substantially fixeddistance at which cover plates 24 and 26 are separated. Flange 46 isrotatable about axis of rotation A and axially disposed between coverplates 24 and 26. Resilient element or springs 42, for transmitting acircumferential or torque force between the flange and the cover plates,are at least partially disposed between cover plates 24 and 26. Springs42 may protrude axially through cover plate openings, referred to hereinas cover plate windows (windows 27 as shown in FIG. 3), to accommodateand position springs 42. Cover plate 26 includes a plurality of ramps 60at or near radially outward surface 72 of the cover plate. Ramps 60 maybe stamped into the cover plate and included integrally or may beotherwise attached or welded onto the cover plate. Ramp 60 protrudesaxially in axial direction AD2 in an example aspect according to FIG. 2.Flange 46 includes tab 50 protruding radially outward from outercircumferential edge 52. Flange 46 includes opening 57 for splineengagement with a transmission input shaft. Ramp engagement occursduring rotation of the flange relative to the cover plates about axis A.As shown for coast mode in FIG. 2, ramp engagement is achieved viarotation in circumferential direction CD1. In another example aspect oralternatively, as one skilled in the art would recognize, ramps arearranged to be included on either the at least one cover plate or flangeso long as that the ramps are engageable to another of the at least onecover plate or flange. Ramps are arrangeable to engage in either coastor drive mode or both. In an example aspect, ramp engagement providesthrust forces to ultimately effect a movement, displacement, ordeflection of the clutch plate so as to engage or close the clutch. FIG.2 further shows gaps g1 and g2. First axial gap g1, having a first widthw1, is disposed between flange 46 and first cover plate 24; and secondaxial gap g2, having a second width w2, is disposed between flange 46and second cover plate 26. At least one of first cover plate 24, secondcover plate 26, or flange 46 comprises at least one ramp 60 protrudingin an axial direction (AD1 or AD2 or both) arranged so that the ramp isrotatably engageable with another of the at least one of first coverplate 24, second cover plate 26, or flange 46 to decrease first axialgap g1 to a third width w3, increase second axial gap g2 to a fourthwidth w4, and transmit an axial force F1 to displace cover plate 26 thusurging a clutch to engage.

In an example aspect, turbine damper assembly 40 comprises cover plate26 including at least one ramp 60 wherein flange 46 rotates about axisof rotation A in a first circumferential direction CD1 relative to firstand second cover plates 24 and 26 in coast mode to rotatably engage theat least one ramp to decrease first axial gap g1 and increase secondaxial gap g2. In another example aspect, flange 46 rotates about axis ofrotation A in second circumferential direction CD2, opposite firstcircumferential direction CD1, in drive mode to rotatably engage atleast one ramp 60 to decrease first axial gap g1 and increase secondaxial gap g2 to increase clutch capacity. In yet another example aspect,second cover plate 26 includes at least one ramp 60 wherein flange 46comprises outer circumferential edge 52 having at least one tab 50protruding therefrom, wherein tab 50 is rotatably engageable with ramp60.

FIG. 3 illustrates a cover plate according to an example aspect. Coverplate 26 includes ramps 60, cover plate windows 27, holes 35 forreceiving rivets (i.e. rivets 31), and opening 70. Cover plates arecontoured as known in the art to house elements of the damper assembly.The number of ramps need not be limited and varies according to designspecifications. In an example aspect, cover plate 26 has at least oneramp 60. In other example aspects, at least two ramps are evenly spacedand disposed on radially outward surface 72. In other example aspects,at least three ramps are evenly spaced around radially outward surface72. In other example aspects and as shown in FIG. 3, at least four rampsare evenly spaced around radially outward surface 72. In other exampleaspects, at least six ramps are evenly spaced around radially outwardsurface 72. In other example aspects, at least eight ramps are evenlyspaced around radially outward surface 72. In other example aspects,cover plate 26 includes at least one ramp and at most twenty ramps.

Features of ramps 60 are tailored to specific needs or to accommodatevarying forces for different torque converter designs. In an exampleaspect, and as shown in FIG. 3, ramps 60 include rise portion 62 (alsoreferred to as first inclined portion 62), second inclined portion 64,and an apex portion 66, which includes rounded, pointed, or flatportions or combinations thereof. Ramps of FIG. 3 include apex portion66 comprising rounded portions and flat portion 67. Portions 62 and 64have equal heights (height h as shown in FIG. 5B). Ramps 60 of coverplate 26 are stamped in an example aspect, leaving voids referred to aspunched out portions 68. While ramps may be formed by other methodsknown in the art, stamping provides the advantage that no more materialis required to form the cover plate including ramps as compared withconventional cover plates.

FIG. 4 illustrates a flange according to an example aspect. Flange 46includes opening 57 and void portions 59 to accommodate and positionsprings 42. Flange 46 includes tabs 50 protruding in a radially outwarddirection from outer circumferential edge 52. Tabs 50 include outercircumferential face 52′, first and second flat surfaces 53 and 54respectively, first side surface 55, second side surface 56, and taperedsurface 58. Tapered surface 58 and flat surface 54 are rotatablyengageable with ramps 60 of cover plate 26 when combined in damperassembly 40.

FIGS. 5A-5C illustrate a slice through a damper assembly according to anexample aspect as viewed near the outer circumference of the assembly inorder to schematically illustrate ramp engagement features at varyingdegrees of rotation. Clutch engagement damper ramps for damper assembly40 are shown in greater detail. FIG. 5A shows ramp 60 of cover plate 26wherein ramp 60 is not engaged with tab 50 of flange 46 having outercircumferential edge 52. Gap g1 represents the space between cover plate24 and flange 46, while gap g2 represents the space between flange 46and cover plate 24. Distance d1 represents the distance between cover 12and flange 46, while distance d2 represents the distance between cover12 and cover plate 26.

As the damper goes into coast mode, flange 46 rotates in circumferentialdirection CD1 relative to cover plate 24 and 26. FIG. 5B shows tab 50and ramp 50 at the moment just before engagement. Gap g1 represents thespace between cover plate 24 and flange 46, while gap g2 represents thespace between flange 46 and cover plate 24. Distance d1 represents thedistance between cover 12 and flange 46, while distance d2 representsthe distance between cover 12 and cover plate 26. Theses distances areunchanged from the condition of damper assembly 40 in FIG. 5A.

As the damper winds up further, flange 46 rotates further incircumferential direction CD1 and tab 50 and ramp 60 slidably contactone another until fully engaged as shown in FIG. 5C and exerting forceF1 on cover plate 26. Gap g1′ represents the space between cover plate24 and flange 46, while gap g2′ represents the space between flange 46and cover plate 24. Note that g1′ is less than g1 and g2′ is greaterthan g2. This is because flange 46 is at a fixed distance d1 from cover12, while cover plate 26 moves towards the turbine in axial directionAD1. Distance d1 remains substantially constant or unchanged inoperation of the torque converter because flange 46 is supported by orthrusts against cover 12. Cover plate 26 is effectively pushed away fromcover 12 due to ramp engagement. Any further rotation of flange 46 indirection CD1 results in maintaining gap g2′ as apex portion 66 includesflat portion 67.

Referring again to FIGS. 1 through 5C, during ramp engagement reactionof flange 46 on cover 12 creates force F1. This force translates intodisplacements and/or deflections capable of closing clutch 15, in otherwords closing clearance 13 to engage clutch plate 23 and apply plate 17as follows: (i) force F1 in turn acts to push or displace cover plate26, as mentioned, in axial direction AD1; (ii) the force on cover plate26 then acts to displace turbine shell 22, also in axial direction AD1,at connection 48; and (iii) then clutch plate 23 is displaced toeliminate clearance 13, the space or gap between clutch and applyplates, and touch apply plate 17. Friction material 25 is optionallydisposed between clutch plate 23 and apply plate 17. In the drivecondition, wherein the clutch is already engaged and clearance 13 equalszero so that no further displacement of turbine shell 22 and clutchplate 23 is possible, turbine shell 22 is further pressed or deflectedso that clutch plate 23 applies more force translating into increasedclutch capacity.

Similarly, ramps are positionable to be engaged when in drive mode, inan example aspect, as flange 46 rotates in circumferential direction CD2(opposite to circumferential direction CD1) thus improving clutchengagement. By incorporating ramp engagement in the drive direction,seals may be advantageously eliminated.

Referring again to FIGS. 1 through 5C, torque converter 10 comprisesaxis of rotation A, cover 12, turbine 20 comprising turbine shell 22 anda plurality of blades 21, impeller 18 comprising impeller shell 16 and aplurality of blades 19, stator 32 comprising a plurality of blades 33.Damper assembly 40 of torque converter 10 further comprises first andsecond cover plates 24 and 26 arranged to receive torque wherein atleast one of the first or second cover plates 24 or 26 has at least oneramp 60 protruding in an axial direction; and, at least one of the firstor second cover plates 24 or 26 thrusts against turbine shell 22 atfastener or rivet 48. Flange 46 thrusts against cover 12 and axiallydisposed between cover plates 24 and 26. Damper assembly 40 furtherincludes at least one resilient element 42, which is at least partiallydisposed axially between first and second cover plates 24 and 26, fortransmitting a circumferential or torque force between flange 46 andcover plates 24 and 26. Torque converter 10 further includes clutch 15including clutch plate 23 and apply plate 17. In an example aspect,flange 46 comprises outer circumferential edge 52 having at least onetab 50 protruding therefrom in a radial direction, wherein tab 50 isrotatably engageable with ramp 60.

In an example aspect, damper assembly 40 further includes first axialgap g1, disposed between flange 46 and first cover plate 24, havingfirst width w1 and second axial gap g2, disposed between flange 46 andsecond cover plate 26, having second width w2. In an example aspect, theat least one ramp 60 is rotatably engageable with flange 46 to decreasefirst axial gap g1, increase second axial gap g2, and transmit axialforce F for urging clutch 15 to engage, in other words, so that clutchplate 23 touches apply plate 17 and clearance 13 is eliminated. In anexample aspect, friction material 25 is disposed between apply plate 17and clutch plate 23, wherein friction material 25 is attached to one ofthe apply plate or the clutch plate or both. In an example aspect,impeller shell 16 includes apply plate 17 and turbine shell 22 includesclutch plate 23.

In an example aspect tab 50 of flange 46 comprises first and second flatsurfaces 53 and 54 respectively, first and second side surfaces 55 and56 respectively having first and second thicknesses t1 and t2, and atleast one tapered surface 58, connecting flat surface 56 to side surface56, wherein tapered surface 58 is rotatably engageable with ramp 60. Inanother example aspect, tab 50 includes two tapered surfaces: one forcoast engagement and an oppositely disposed tapered surface for driveengagement. In an example aspect, ramp 60 further includes apex portion66 and at least one rise portion 62, wherein rise portion 62 isrotatably engageable with tapered surface 58. In an example aspect, apexportion 66 includes flat portion 67 for maintaining engagement with tab50. In an example aspect, flange 46 thrusts against cover 12.Optionally, flange 46 and cover 12 further include bushing 44, thrustwasher 28, or both disposed therebetween. In an example aspect flange 46is arranged for direct connection to a transmission input shaft. In anexample aspect flange 46 is rotatable in a first circumferentialdirection CD1 in coast mode to engage ramp 60, react on cover 12, andmove at least one of first or second cover plates 24 or 26 to displaceturbine shell 22 in axial direction AD1 towards impeller 18 thus urgingclutch plate 23 to touch apply plate 17. In another example aspect,flange 46 is rotatable in second circumferential direction CD2, oppositeto first circumferential direction CD1, in drive mode to engage ramp 60,react on cover 12, and move at least one of first or second cover plates24 or 26 to press turbine shell 22 in axial direction AD1 againstimpeller 18 thus increasing clutch capacity. In yet another exampleaspect, torque converter 10 includes ramps 60 engageable in both driveand coast modes.

In an example aspect torque converter 10 comprises axis of rotation A,turbine 20 comprising turbine shell 22 and plurality of blades 21,impeller 18 comprising impeller shell 16 and a plurality of blades 19;housing 7 comprising cover 12 and impeller shell. Torque converter 10further comprises stator 32 comprising a plurality of blades 33, anddamper assembly 40 comprising cover plates 24 and 26 arranged to receivetorque; flange 46 rotatable about axis of rotation A, thrusts againstcover 12, and axially disposed between first and second cover plates 24and 26. Damper assembly 40 further comprises at least one resilientelement or spring 42, which is at least partially disposed axiallybetween first and second cover plates 24 and 26, for transmitting acircumferential or torque force between flange 46 and cover plates 24and 26. In an example aspect, at least one of first cover plate 24,second cover plate 26, or flange 46 includes at least one ramp 60protruding in an axial direction, wherein ramp 60 is rotatablyengageable with another of the at least one of first cover plate 24,second cover plate 26, or flange 40. In an example aspect, torqueconverter 10 includes damper assembly 40 having first axial distance d1,as measured between inner surface 9 of cover 12 and a first radialsurface 73 of flange 46, wherein axial distance d1 remains constant orunchanged as ramp 60 is rotatably engaged; and second axial distance d2,as measured between inner surface 9 of cover 12 and second radialsurface 72 (also referred to a radially outward surface 72interchangeably herein) of the cover plate 26, wherein axial distance d2increases as ramp 60 is rotatably engaged. Torque converter 10 furthercomprises clutch 15 including clutch plate 23 and apply plate 17.

In an example aspect, turbine shell 22 of torque converter 10 is fixedto cover plate 26 and, as ramp 60 is rotatably engaged, cover plate 26is displaced in axial direction AD1 towards impeller 18. In an exampleaspect, turbine shell 22 includes clutch plate 23. In an example aspect,clutch 15 of torque converter 10 is engaged as ramp 60 is rotatablyengaged.

FIG. 6A shows a partial cross-sectional view of damper assembly 40 ashowing flange 46 a disposed between two cover plates, 24 a and 26 a, inan example alternative aspect. FIG. 6B shows a partial top view ofdamper assembly 40 a wherein cover plate 26 a is lanced forming ramp 60a. Both cover plate 26 a and flange 46 a are lanced and are formed tothe outside of the damper assembly thereby forming two ramps 50 a and 60a, that when the damper is assembled, will react with each other in thecoast direction causing axial movement of the piston towards theimpeller in a torque converter similar to that shown in FIG. 1 (i.e.piston 23, impeller 18 of FIG. 1).

FIG. 7 shows a partial cross-sectional view of damper assembly 40 bshowing cover plate 26 b is lanced and flange 46 b is coined in anexample alternative aspect. Cover plate 26 b is lanced and formed to theoutside of damper 40 b to form ramp 60 b. Flange 46 b is coined to formramp 50 b. Ramps 60 b and 50 b interact or engage in the coast directioncausing axial movement of the piston towards the impeller as previouslydescribed. In an example aspect, flange ramp 50 b is stiffer than flangeramp 50 a, for example, providing for a more predictable axial load forimproved durability.

FIG. 8A shows a partial cross-sectional view of damper assembly 40 cshowing flange 46 c disposed between two cover plates, 24 c and 26 c, inan example alternative aspect. FIG. 8B shows a partial top view ofdamper assembly 40 c wherein cover plate 26 c is lanced to formelongated finger ramp 60 c. Flange 46 c is also lanced to form ramp 50 cengageable with finger ramp 60 c. Finger ramp 60 c acts as a spring asramp 50 c pushes against it. As a result of the engagement of ramps 50 cand 60 c, cover plate 24 c is then displaced sufficiently to engage thepiston while the load is only dependent on the spring force. Thisadvantageously enables the damper to still wind up in coast with theaddition of hysteresis added by the contact between the flange and rampfinger 60 c.

FIG. 9 shows a cross-sectional view of a torque converter includingturbine damper assembly 140 comprising a hardened ramp plate in anexample aspect. Hardened ramp plate 125 is also referred tointerchangeably herein as plate 125. Elements common to torque converter10 of FIG. 1 and torque converter 110 of FIG. 9 are numbered similarly.Torque converter 110 comprises axis of rotation A, flange 146 rotatableabout axis A, turbine shell 122 independently rotatable about axis ofrotation A relative to flange 146, and plate 125, which is disposedbetween flange 146 and turbine shell 122. Hardened ramp plate 125 isfixed to turbine shell 122 at weld or rivet 148. Torque converter 110further comprises plate 126, which may be a cover plate, disposedbetween flange 146 and turbine shell 122. Plate 126 is radially outwardrelative to plate 125 as shown in FIG. 9, or alternatively, plate 125passes under plate 126 or through plate 126 in lower travelapplications. Torque converter 110 further comprises cover 112 havinginner surface 109 and plate 124, which is disposed between flange 146and cover 112. Torque converter 110 further comprises at least oneresilient element 142, which is at least partially disposed axiallybetween plates 124 and 126 and is radially outward relative to plate125, for transmitting a torque force between flange 146 and plates 124and 126. In an example aspect, torque converter 110 further includesanother resilient element 143 and pendulum damper 144, both radiallyoutward relative to resilient element 142. Torque converter 110 includesflange hub 131 and bushing 130.

Referring to FIGS. 9 and 10, torque converter 110 further comprisesaxial gap g3, disposed between flange 146 and plate 126, having widthw3; and, axial gap g4, disposed between flange 146 and plate 124, havingwidth w4. Plate 125 includes at least one ramp 160 protruding in axialdirection AD2 toward flange 146, wherein ramp 160 is rotatablyengageable with flange 146 for urging flange 146 axially in directionAD2 toward cover 112, and for transmitting an axial force for urgingclutch 115 to engage. In an example aspect plate 124 includes radiallyoutward portion 124′ disposed between two pendulum masses P1 and P2.

In an example aspect, plate 125 is stamped and hardened. In an exampleaspect, plate 125 is fixed to turbine shell 122 via weld or rivet 148.In an example aspect, plate 125 is annular and is cut or lanced tointegrally form the at least one ramp 160 having axial height hi asshown in FIG. 11, which is a perspective view of plate 125. In anexample aspect, flange 146 is rotatable about axis of rotation A incircumferential direction CD1 relative to plates 124 and 126 to engageramp 160. In an example aspect, flange 146 is rotatable about axis ofrotation A in circumferential direction CD2, opposite circumferentialdirection CD1, to engage the at least one ramp 160 to increase clutchcapacity. FIG. 12 shows a top view of flange 146 as in an exampleaspect. Flange 146 includes openings 128 including flange ramps 129 forengaging with ramps 160 of plate 125.

FIG. 13 shows a cross-sectional view of torque converter 210 wherein theturbine damper assembly 240 includes coast engagement ramp plate 225.Coast engagement ramp plate 225 is also referred to interchangeablyherein as plate 225. Elements common to torque converters 10, 110, and210 are numbered similarly. Torque converter 210 includes plate 226 isfixed to turbine shell 222. In an example or alternative aspect, plates225 and 226 are integrally formed. Torque converter 210 furthercomprises axis of rotation A, flange 246 rotatable about axis A, turbineshell 222 independently rotatable about axis of rotation A relative toflange 246, and plate 225, which is disposed between flange 246 andturbine shell 222. Hardened ramp plate 225 is fixed to turbine shell 222at weld or rivet 248. Torque converter 210 further comprises plate 226,which may be a cover plate, also disposed between flange 246 and turbineshell 222. Plate 226 is at least partially radially outward relative toplate 225 as shown in FIG. 13, or alternatively, plate 225 is integrallyformed with plate 226 in alternative example aspects. Torque converter210 further comprises cover 212 having inner surface 209 and plate 224,which is disposed between flange 246 and cover 212, and which may alsobe a cover plate. Torque converter 210 further comprises at least oneresilient element 242, which is at least partially disposed axiallybetween plates 224 and 226 and is radially outward relative to plate225, for transmitting a torque force between flange 246 and plates 224and 226.

Referring to FIGS. 13 and 14, torque converter 210 further comprisesaxial gap g5, disposed between flange 246 and plate 226, having widthw5; and, axial gap g6, disposed between flange 246 and plate 224, havingwidth w6. Plate 225 includes at least one ramp 260 protruding in axialdirection AD2 toward flange 246, wherein ramp 260 is rotatablyengageable with flange 246 for urging flange 246 axially in directionAD2 toward cover 212, and for transmitting an axial force for urgingclutch 215 to engage.

In an example aspect, plate 225 is fixed to turbine shell 222 via weldor rivet 248. In an example aspect, flange 246 is rotatable about axisof rotation A in circumferential direction CD1 relative to plates 224and 226 to engage ramp 260. In an example aspect, flange 246 isrotatable about axis of rotation A in circumferential direction CD2,opposite circumferential direction CD1, to engage the at least one ramp260 to increase clutch capacity. Flange 246 includes flange ramps 229for engaging with ramps 160 of plate 125 as shown in FIG. 14,illustrating flange 246 engagement with ramp 260 along line B-B′ of FIG.13.

In another example aspect, and as shown in FIGS. 1-14 torque converter(10, 110, 210) comprises axis of rotation A, first and second coverplates (24, 26; 124, 126) arranged to receive torque; flange (46, 146)rotatable about axis of rotation A; turbine shell (22, 122, 222)independently rotatable about axis of rotation A relative to flange (46,146); an optional plate (125, 225), disposed between flange (46, 146)and turbine shell (22, 122, 222), fixed to turbine shell (22, 122, 222)and arranged to receive torque; at least one resilient element (42,142), at least partially disposed axially between the first and secondcover plates (24, 26; 124, 126) and radially outward relative to thethird plate (125, 225), for transmitting a torque force between betweenflange (46, 146) and first and second cover plates (24, 26; 124, 126);first axial gap (i.e. g1), disposed between flange (46, 146) and firstcover plate (26, 126), having first width (i.e., w1); second axial gap(i.e. g2), disposed between flange (46, 146) and second cover plate (24,124), having second width w2; one of first cover plate (26, 126), secondcover plate (24, 124), or third plate (125, 225) having at least oneramp (60, 160, 260) protruding in an axial direction toward flange (46,146), the ramp rotatably engageable with flange (46, 146) for urgingflange (46, 146) axially in a direction toward cover (12, 112), and fortransmitting an axial force for urging clutch (15, 115) to engage.

Of course, changes and modifications to the above examples of thepresent disclosure should be readily apparent to those having ordinaryskill in the art, without departing from the spirit or scope of thepresent disclosure as claimed. Although the present disclosure isdescribed by reference to specific preferred and/or example embodiments,it is clear that variations can be made without departing from the scopeor spirit of the present disclosure as claimed.

What we claim is:
 1. A torque converter comprising: an axis of rotation;a flange rotatable about the axis of rotation; a turbine shellindependently rotatable about the axis of rotation relative to theflange; a first plate, disposed between the flange and the turbineshell, fixed to the turbine shell; a second plate, disposed between theflange and the turbine shell, radially outward relative to the firstplate; a cover having an inner surface; a third plate, disposed betweenthe flange and the cover; at least one resilient element, at leastpartially disposed axially between the second and third plates andradially outward relative to the first plate, for transmitting a torqueforce between the flange and the second and third plates; a first axialgap, disposed between the flange and the second plate, having a firstwidth; a second axial gap, disposed between the flange and the thirdplate, having a second width; and the first plate having at least oneramp protruding in an axial direction toward the flange, the ramprotatably engageable with the flange for urging the flange axially in adirection toward the cover, and for transmitting an axial force forurging a clutch to engage.
 2. The torque converter of claim 1, whereinthe first plate is stamped and hardened.
 3. The torque converter ofclaim 1, wherein the first plate is fixed to the turbine shell via aweld or a rivet.
 4. The torque converter of claim 1, wherein the firstplate is an annular plate and is cut or lanced to integrally form the atleast one ramp having a first axial height.
 5. The torque converter ofclaim 1, wherein the flange is rotatable about the axis of rotation in afirst circumferential direction relative to the second and third platesto engage the at least one ramp.
 6. The torque converter of claim 5,wherein the flange is rotatable about the axis of rotation in a secondcircumferential direction, opposite the first circumferential direction,to engage the at least one ramp to increase clutch capacity.
 7. Thetorque converter of claim 1, wherein the second plate is fixed to theturbine shell.
 8. The torque converter of claim 7, wherein the first andsecond plates are connected to each other via a rivet or a weld.
 9. Thetorque converter of claim 1, wherein the second width of the secondaxial gap is greater than the first width of the first axial gap.
 10. Atorque converter comprising: an axis of rotation; first and second coverplates arranged to receive torque; a flange rotatable about the axis ofrotation; a turbine shell independently rotatable about the axis ofrotation relative to the flange; a third plate, disposed between theflange and the turbine shell, fixed to the turbine shell; at least oneresilient element, at least partially disposed axially between the firstand second cover plates and radially outward relative to the thirdplate, for transmitting a torque force between the flange and the firstand second cover plates; a first axial gap, disposed between the flangeand the first cover plate, having a first width; a second axial gap,disposed between the flange and the second cover plate, having a secondwidth; and one of the first cover plate, the second cover plate, or thethird plate having at least one ramp protruding in an axial directiontoward the flange, the ramp rotatably engageable with the flange forurging the flange axially in a direction toward the cover, and fortransmitting an axial force for urging a clutch to engage.
 11. Thetorque converter of claim 10, wherein the flange is rotatable about theaxis of rotation in a first circumferential direction relative to thefirst and second cover plates to engage the at least one ramp todecrease the first axial gap and increase the second axial gap.
 12. Thetorque converter of claim 11, wherein the flange is rotatable about theaxis of rotation in a second circumferential direction, opposite thefirst circumferential direction, to engage the at least one ramp todecrease the first axial gap and increase the second axial gap toincrease clutch capacity.